Japanese Patent Application Laid-Open Publications Nos. 57(1982)-84249, 58(1983)-39551 and 5(1993)-319245 disclose hydraulic braking devices that include a power hydraulic pressure source and a master cylinder which is operatively connected to a brake pedal. In this hydraulics brake device, the hydraulic pressure having a magnitude corresponding to the depressed force of the brake pedal is applied from the power hydraulic pressure source to the wheel brakes when the power hydraulic pressure source is in the normal condition, and the hydraulic pressure in applied from the master cylinder to the wheel brakes when the power hydraulic pressure source is in the abnormal condition. This hydraulic brake device further includes a pedal stroke simulator for generating a stroke of the brake pedal corresponding to the depressed force applied to the brake pedal when the power hydraulic pressure source is in the normal condition.
In the devices described above, however, the brake pedal does not move unless the piston of the pedal stroke simulator and the pistons of the master cylinder begin to slide, and the load or force required to make the pistons of the pedal stroke simulator and the master cylinder begin to slide is relatively high. As a results an operational feeling of the brake pedal deteriorates.
In light of the foregoing, a need exists for a master cylinder and hydraulic braking device that are not as susceptible to the same disadvantages and drawbacks as described above.
It would be desirable to provide a master cylinder and hydraulic braking device in which the operational feeling of the brake pedal is not diminished.